How to Prevent Early Ovulation/Luteinization During an IVF Cycle

In ovarian stimulation for artificial reproductive medicine, we sometimes encounter progesterone elevation (PL; Premature luteinization) on the day of ovulation trigger. Higher progesterone levels on the ovulation trigger have been indicated to induce adverse effects in pregnancy and implantation. This effect’s mechanism is considered an asynchrony between the embryo and the endometrium. PL is commonly defined as an elevation of serum progesterone over 1.5 ng/ml; however, the threshold values differ from the studies. PL had been evaluated by several predictors such as a single progesterone level, progesterone/ estradiol ratio, and progesterone/oocyte ratio. Some conditions may easily induce PL. In poor responder patients, a higher dose of FSH is used and that hormonal milieu provides a condition for premature luteinization. The physiological mechanism for PL has been studied; however, it is yet clarified. Since PL occurs during ovarian stimulation, FSH administration may contribute to PL. HCG trigger timing may also be an essential factor in raising progesterone. In the cases of premature luteinization, the freeze-all can be an appropriate means to keep pregnancy possibility. On the other hand, some studies indicate that the low success rates are attributable to the low quality of the embryo, not to hormonal or endocrinological disturbances. In this theory, the freeze-all strategy is not enough for a solution. Concerning impaired endometrium receptivity induced at premature luteinization, it has been reported to cause implantation failure. It has been indicated that PL affects pregnancy and live birth rates. Therefore, we are required to prevent PL by selecting appropriate ovarian stimulation protocol to achieve high pregnancy rates, optimal trigger timing, and use of medications such as corticosteroids or metformin that may prevent PL.